Cutter head for shaving machines



July 2, 1940.

A. G. STEVENSON CUTTER HEAD FOR SHAVING MACHINES Filed May 7, 1938 11v VENTOR BI |G 3 Amww? GnSTEVE/KSON 'FIGIE A TTOENE y Patented July 2, 1940 This invention relates to shaving machines and has for its object to provide a novel form of cutter head for sucha machine.

Another object of this invention is to provide the cutter head with a novel shear-member. I

A further object of this invention is to provide the cutter oi. the cutting head with novel cutting edges for cooperation with the shear-member. A still further object 01' this invention is to provide a novel construction for the drive of the shear-member.

All these and other objects and attendant advantages of this invention will become more readily apparent from the detailed description thereoi' which follows, reference being had to the accompanying drawing in which Figure 1 is a top plan view of the'shaving machine embodying the new and improved cutter head.

Figure 2 is a side elevation thereof.

Figure 3 is an end elevation thereof.

Figure 4 is a detail view of the cutter member of the cutter head.

Figure 5 is an end elevation of the cutter member.

- Figure 61s a longitudinal sectional view or the cutter member taken on the line iaa-Cm'of Figure 4. v 1

Fi ure 7 is a cross section of the cutter member taken on the line Iw- --|a: oi' Figure 6.

Figure 8 is a detail view of the shear-member of the cutter head. ,Figure 9 is an end elevation member.

. Figure 10 is a longitudinal sectional view oi the shear-member taken on the line Ila-Illa: of Figure 8. I

Figure 11 is a cross section of the shear-member taken on the line llx-l Ix of Figure 10.

Figure 12 is an enlarged cross section oi the cutter head taken on the line Ila-I2: of Figure 3.

of the shear- Figure 13 is an enlarged longitudinal section of the cutter head taken on the line lit-"x of Figure 3.

Figure 14 is an enlarged section of the cutting edges. of the cutter member of the cutter head as they appear when placed against the beard for shaving.

In the several figures or the drawing like reference numerals indicate like parts.

The shaving machine embodying the subject matter of my present invention is provided with f l a suitable driving motor encased in the handle I t I and provided with a drive I. The latter carries a ball member 3 which is eccentrically mounted on the tapered shank 4 to thus provide a ball crank for the operation 01' the cutter head as will hereinafter appear. At the outer end of the handle I is formed the semi-cylindrical cradle or seat 5 adapted to have the cutter head removably mounted therein.

The cutter head comprises the cylindrical cutter member 6 which is provided with an eccentrically located longitudinally extending cylindrical I0 bearing 1 in which is mounted to oscillate the shear member 8. The eccentric arrangement 01' the bearing 1 provides in the cylindrical cutter member at diametrically opposite sides a thin and a thick wall, of which the thin wall is longitudinally slotted and then hollow or concavedly ground to provide the razor'edges 9 and ID on 4 opposite sides of the slot. 1

In the thick wall of the cutter member are provided a pair or holes II, .II which are threaded to receive suitable mounting screws I 2, l2 with which the cutter head is removably mounted in the seat or cradle 5 01' the handle. Extending thru the middle of the thick wall of the cutter member is a large opening it which is adapted to have the ball crank of the drive shaft project therethru for the engagement and operation of the shear-member l.

The shear-member;comprises a longitudinally grooved and transversely slotted cylindrical member in order to provide the wide longitudinal groove H for the engagement oi the ball crank and the narrow groove HA diametrically opposite to the groove I for the spacing of the two rows of parallel shear fingers l5, I! which are adapted to cooperate with the razor edges of the cutting member. The transverse slots l6, which space the shear fingers longitudinally, are arranged so as to stagger the shear fingers in one row from the shear fingers in the other row. In this way the cooperative action oi one row of shear fingers with one razor edge supplements the cooperative action of the other row of shear fingers with the opposite razor edge. The hairs projecting between the cutting edges oi the cutting member will thus be severed by the action oi! a shear finger from either one or the other row of these fingers. Tia lateral spacing of the shear fingers together with their peripheral spacing provide a maximum unobstructed space for the hairs to project into the cutting member which, with the comb eiiect produced byeach row or shear fingers. cause the hairs to be moved into an erect position against either one or the other of the razor edges to be severed thereon p i when the shear fingers force the hairs against hair or a beard which has not been allowed to grow too long may erect itselfor be moved into an erect position by the shear fingers to be. forced against one or the other of the razor edges and severed thereby close to the skin.

As the cutter head is moved over the skin while being 'yieldingly. held thereagainst small sections ofthe entire surface or the skin are continuously molded into the cutter head between the razor edges. This causes the hairs on'the skin to yieldingly spring and project into the .space between the razor edges to be forcedagainst and severed by either one or the other of these edges on the oscillating movement of the shear fingers.

For the purpose of yieldingly holding the shear fingers against the inside of the cutter member so as to produce an efiicient shearing action be tween them and the razor edges, anelongated spring 20- is located in the groove i4 and held against endwise movement therein by theengagement of its ends into suitable indentations 2|, 2| in the shear member. The ball member I thus rests against and moves over this spring and thereby exerts at all times a yielding pressure against the shear member for the shearing action between it and the razor edges.

The longitudinal grooves 22, 22 which extend across the shear fingers oi the shear member on substantially opposite sides thereof provide suitable space for the insertion oi! a cleaning rod irom one end to the other or the cutter head.

The ends of the seat or cradle 5 in which the Z cutter head is mounted are closed by the retaining plates 23 and partially' extend overthe ends of the cutter 'head so as to hold the shear member against endwise movement therein and by removing one of these end plates the shear member may thus be removed from the cutter D head for cleaning.

aaoas'ss Iclaim: 1. A tubular cutter head for shaving ma- .chines having a longitudinal slot therein, a hollow ground razor edge provided on the longitudinally extending opposing edges of said slot so as to convexedly shape the skin toward said razor edges, andra shearing member mounted to oscillate in said cutter head, a longitudinal slot in said shearing member, transversely extending slots terminating from opposite sides into said longitudinal slot with the transverse slots on one side being staggered relative to the slots on the other side of said longitudinal slot to provide two rows of transversely spaced cutting fingers on said shearing member with the cutting fingers oi one row being staggered relative to the cutting fingers or the other row.

2. A tubular cutter head for shaving machines having a longitudinal slot therein, a hollow ground razor edge provided on the longitudinally extending opposing edges of said slot so as to convexedly shape the skin toward the slot in the cutter head. a cylindrical shear member mounted to oscillate within said tubular cutter head, a longitudinal slot in said shear member, transverseslots extending from thesidesoi said shear member into said longitudinal slot, said transverse slots being arranged on opposite sides of said longitudinal slot so as toiorm two rows 0! longitudinally and circumferentiallyspacedshear fingers with the fingers in one row being staggered relative to the fingers in the other row.

3. A tubular cutting head as set forth in claim 2 including a second longitudinal slot in said shear member, a ball crank projecting into said second slot and a single spring member interposed between the end of said ball crank and said shear member and extending longitudinally of said second slot to yieldingly hold said shear member for shearing action with said razor edges the full lengththereot on the rotation of said ball crank. I

4. A tubular cutting head as set forth in claim 1 andprovided with longitudinal grooves at the bottom of the two rows of shear fingers so as to receive the severed hair and permit the expulsion thereof from the shear member I from the ends or the cutting head.

ARTHUR G. s'rmvnnson. I0 

